Apple's macOS High Sierra has a terrifying security flaw which lets anybody hack your system - in the easiest way possible.

Security researchers discovered the bug and revealed the flaw to the public yesterday.

Staggeringly for such a sophisticated company, Apple appears to have made a device incredibly susceptible to hacking.

Anyone who hits a prompt in High Sierra asking for a username and password before logging into a machine with multiple users can simply type "root" as a username, leave the password field blank, click "unlock" twice, and immediately gain full access.

The bug, which was discovered by Turkish developer Lemi Ergin, has led to widespread panic among device users.